In general, the present invention relates into a mechanism for opening and closing a shutter for blocking a window for inserting a storage medium employed in a removable storage medium devices such as an optical disk drive. In particular, the present invention relates to a shutter opening/closing mechanism for improving a dust-prevention characteristic.
The shutter opening/closing mechanism of this type is intended for use in preventing dust and foreign material from being introduced into a removable storage medium device from the air.
FIG. 4 is a diagram showing a cross section of a typical conventional shutter opening/closing mechanism which is referred to hereafter as a first conventional example. A shutter 3 is rotatably installed at an insert window of a front mask 5 on the front surface of an optical disk drive. The shutter 3 is pressed against an inner surface of the front mask 5 by a shutter spring 6. In this configuration, the insert window is blocked by the shutter 3 to prevent dust from being introduced into the optical disk drive before a cartridge is inserted thereto.
In addition, disclosed in Japanese Patent Laid-open No. Hei 5-234210 is a technology for blocking an insert window in order to prevent dust from being introduced into a storage device wherein a cartridge load mechanism is used for moving a shutter up and down so that the insert window is blocked before and after a cartridge is inserted into the insert window. This shutter opening/closing mechanism is referred to hereafter as a second conventional example.
Disclosed in Japanese Patent Laid-open No. Hei 5-205456 is a technology wherein, an insert window is opened by pressing a cartridge against a door and the insert window is blocked by the door after the insertion of the cartridge so that dust is prevented from being introduced into the storage device. This shutter opening/closing mechanism is referred to hereafter as a third conventional example.
In the case of the first conventional example, however, even though the insert window is blocked by the shutter 3 before a cartridge 8 is inserted, a portion of the shutter 3 is brought into contact with the cartridge 8 after the cartridge 8 has been inserted as shown in FIG. 5, causing the insert window to be closed incompletely. As a result, dust may be introduced into the storage device by way of a gap between the shutter 3 and the insert window. The introduction of dust gives rise to a problem that the dust is stuck to optical components and a disk, degrading the read/write performance.
In the case of the second conventional example, on the other hand, the configuration thereof is such that the shutter blocks the insert window after a cartridge has been inserted so that the problem with the first conventional example described above is solved. However, a mechanism for moving the shutter up and down is embedded in a load mechanism, giving rise to a problem that the mechanism becomes complex and the work to assemble it becomes difficult. There is also another problem that, in spite of the fact that the power of the load mechanism is limited by the driving power of a motor, the load mechanism can not be driven manually.
In the case of the third conventional example, since the power for opening and closing the shutter does not depend on the load mechanism, the problems with the second conventional example described above are solved. However, a space must be reserved for the locus of the rotating movement of the door, giving rise to a space problem. On top of that, the third conventional example has such a configuration that by pushing the cartridge in a horizontal direction the door is moved away in a slanting direction. In addition, a component of a force for pressing the cartridge toward a rotational shaft exists so that a greater force is required for pressing the cartridge, giving rise to a problem that the user feels a sense of incongruity and an operational problem that the cartridge is difficult to press.